[1] Harrop attended the Medical School of the Johns Hopkins University and received his Doctorate of Medicine in 1916.

[1] Harrop invented the banana and skimmed milk diet for weight loss in obese patients.

The diet recommended taking six bananas with 1000 cubic centimetres (4 glassfuls) of skimmed milk each day.

[3] Harrop recommended adding eggs, fish and lean meat to the diet after ten days.

[7][8] Physician Morris Fishbein commented that "many people found it difficult to follow because they could not tolerate milk and the diet was also criticized because of its tendency to produce constipation.